The invention relates to a rail having at least one running surface for bearing rollers of running mechanisms, which rail is formed by at least two successive profile pieces of equal cross-section, which join together at a junction point, and comprises at least one coupling piece, which overlaps and is connected to two adjoining profile pieces. Each profile piece has, for receiving that part of a coupling piece which overlaps it, a coupling groove, with lateral holding strips, which overlap the coupling piece with holding surfaces, and in that the part of the coupling piece is braced against the holding surfaces by means of at least one threaded pin, which is screwed into a through bore of said coupling piece and presses against the floor of the coupling groove. Rails of this type serve the guidance of running mechanisms which bear sliding doors, for example external and internal doors on buildings and also furniture doors.
The rails comprise a plurality of straight or curved, usually extruded profile pieces of equal cross-section made from metal, generally aluminium. In this case, the connection of successive profile pieces often presents certain difficulties, since the said profile pieces should join together, at the junction points, as exactly congruently as possible, whilst, at the same time, the connection should be able to be created, in the assembly, rapidly and without difficulty.
It is known to connect successive profile pieces by means of tongues which overlap both and are screw-connected to both profile pieces. Such a connection is however awkward in the assembly and requires a plurality of very accurately placed bores.